PROBLEM TO BE SOLVED: To provide a subject information acquisition device capable of constituting ultrasonic images of high azimuth resolution while suppressing a processing scale.SOLUTION: The subject information acquisition device to be used includes: a probe including a plurality of conversion elements for receiving acoustic waves emitted from a subject and converting them into reception signals; a phasing delay unit for matching phases of the plurality of reception signals output from the plurality of conversion elements; signal addition means for adding the plurality of reception signals output from the phasing delay unit for each group to obtain latter stage input signals; and an adaptive signal processing unit for generating internal image data of the subject by performing adaptive signal processing on the plurality of latter stage input signals output from each of the plurality of signal addition means.【課題】方位分解能が高い超音波画像を、処理規模を抑制しつつ構成可能な被検体情報取得装置を提供する。【解決手段】被検体から放出された音響波を受信して受信信号に変換する複数の変換素子を含むプローブと、複数の変換素子から出力される複数の受信信号の位相を揃える整相遅延部と、整相遅延部から出力された複数の受信信号をグループごとに加算して後段入力信号とする信号加算手段と、複数の信号加算手段のそれぞれから出力された複数の後段入力信号に適応型信号処理を行い被検体内部の画像データを生成する適応型信号処理部を有する被検体情報取得装置を用いる。【選択図】図1